Automobiles, and particularly stock car type racing automobiles, use Timken® style tapered roller bearings mounted in the wheel hubs. Grease seals are used in the hubs to retain lubricating grease in the bearing cavity and prevent such grease from escaping the wheel hub and fouling brake components, tires, the track, etc. The seals are usually press fitted into an internal bore in the hub and locked in place by an internal snap ring fitted in a groove in the internal bore of the hub. See FIG. 5 (Prior Art) which shows a standard hub 10 having an internal bore 12, flange 14 acting as a stop for grease seal 16, and an internal groove 18 for receiving snap ring 20 to retain grease seal 16 in the hub 10. In a typical example, the seal is 0.375″ wide, with an OD of 3.5″ and seals against a 2.375″ seal surface on a 2″ diameter spindle. The seal is typically a 0.005″ press fit in the internal bore 12 of the hub 10.
Due to the extreme conditions under which these vehicles operate, the bearings are removed from the hub, cleaned and repacked with grease after every race. However, to do this, the seals must first be removed from the hubs to allow access to the bearings. Because the seals are press fitted into the hub, removal of the seals, by prying them out of the hub with a pry bar or other tool, usually damages the seals so that they can no longer be used. Thus, the four seals on the four hubs must be replaced after every race, even though they were still in good condition prior to being removed from the hubs. This results in additional expense for replacing several dozen seals over the course of a racing season that were rendered unusable only by virtue of having to remove them from the hub to grease the bearings.
In addition, the act of removing the seals with a pry bar is not precise and can result in gouging or otherwise damaging the hub, especially an aluminum or magnesium hub, potentially requiring replacement of the hub. Injury to the mechanic can also occur.